Attacking Alzheimer’s: A Conversation with Jim Sullivan
Jim Sullivan, Ph.D., vice president for discovery at AbbVie, explains why Alzheimer’s disease is so difficult to treat and what AbbVie is doing to uniquely target the disease.
Jim Sullivan, Ph.D., vice president for discovery at AbbVie, leads a global team of dedicated scientists and researchers who work to identify potential new medicines. His team involves a wide range of scientific disciplines, including biology, chemistry and pharmacology. Here Jim explains why Alzheimer’s disease is so difficult to treat, what AbbVie is doing to uniquely target the disease, and why the need for treatments for all types of dementia is growing exponentially.
Nearly 47 million people worldwide are living with dementia — and over the next few decades that number is projected to double every 20 years. Alzheimer’s is the most common form of dementia, and aging is its biggest risk factor. If we all live to the age of 85, one in two of us will develop dementia.
These numbers tell us that Alzheimer’s represents a huge challenge for society as the number of patients and caregivers seeking help from the health care system will explode in the coming decades. Just as importantly, from a research and development perspective there have been a number of significant advances in our understanding of the disease. This coupled with the availability of new imaging tools that are helping us better understand the disease and also investigate potential treatments, present us with promising scientific opportunities.
How is it treated today?
It’s not. Treatments available at the moment simply address the cognitive symptoms and do nothing to prevent the progression of the disease or reverse the damage. So while these treatments may work for a while, their effect quickly wears off. This is because the disease continues to progress and patients reach a point when they don’t have enough healthy neurons for the treatments to act on.
How has Alzheimer's research progressed over the years?
More than 100 years ago, pathologist Alois Alzheimer examined the brains of people with dementia and discovered clumps of protein in the cortex and the hippocampus. Known as amyloid plaques, those clumps make up another protein called beta-amyloid. Dr. Alzheimer also identified clumps within neurons called tangles that decades later were determined to be made up of a second crucial protein called tau.
Recently it has been discovered that the formation of these beta-amyloid plaques and tangles starts to occur when people are as young as in their 40s. This process begins fairly slowly, but it is constant and unrelenting. Over time, the accumulation of amyloid and tangles disrupts the way neurons communicate with each other, ultimately causing their death. That’s when you see the symptoms of the disease.
There have been a number of other scientific breakthroughs that have occurred during the last few decades. For example, genetic studies have pointed to a role of the brain’s immune system in the progression of the disease. It’s all these breakthroughs that make this a good time to focus on this area.
So the damage is done long before the patient becomes symptomatic?
Exactly. In heart disease, we know enough to identify warning signs, like elevated cholesterol, and can treat before the patient is symptomatic. With Alzheimer’s it’s not that simple.
We know now that there is a pre-symptomatic phase when patients don’t show cognitive decline that could last for 10 years or more. So when patients start showing mild cognitive impairment, for example forgetting words, it indicates significant damage. Over time, moderate cognitive impairment becomes severe. This is when patients start showing the signs of severe dementia and the behaviors associated with it, like agitation and aggression.
How are you looking at treating Alzheimer’s?
Our understanding of Alzheimer’s has increased significantly in recent years. There are new tools available — imaging and biomarkers — that can help us not only understand the disease but also identify patients and evaluate the effects of potential drugs early in clinical development. We are also taking advantage of the recent scientific insights to identify innovative new approaches. For example, many patients with Alzheimer’s have significant accumulation of a protein called tau so we’re looking at how we can potentially block this accumulation and spreading early on in the disease.
We are also working some of the most well-known experts in the field, with a number of external teams at academic institutions, including Mass General Hospital, Washington University in St. Louis, and University of Cambridge, as well as co-leading the European Union’s Innovative Medicines Initiative ADAPTED (Alzheimer's Disease Apolipoprotein Pathology for Treatment Elucidation and Development) Project.
Many companies have been getting away from pursuing Alzheimer’s treatments. Why jump into a field that others are avoiding
We are in this for the long haul. In 2016, we opened a 43,000-square-foot Foundational Neuroscience Center (FNC) in the Cambridge, Massachusetts, U.S.A., biotech corridor where we are performing research to gain a deeper understanding of the biological mechanisms underlying neurodegenerative diseases, in particular Alzheimer’s disease. We recently hired internationally renowned Alzheimer's expert, Eric Karran, Ph.D., vice president, Foundational Neuroscience Center, to help lead this center.
Finding new treatments for Alzheimer’s has enormous potential to make a remarkable impact on in the lives of patients and their caregivers. That’s why we’re committed to Alzheimer’s research for the long term.